The General Services Administration (GSA), the US federal government’s landlord, has said the US Green Building Council’s Leadership in Energy and Environmental Design (LEED) system to be the most credible among five different systems evaluated for its projects including BREEAM.

However, David Strong MD of BRE Environment told Sustainable Building there was little to be gained from debating the relative strengths of the two systems which had, after all, been developed for two quite different markets.

However, he noted that 66,000 buildings have been assessed in the UK alone under the BREEAM and Eco-Homes standards, whereas less than 400 buildings worldwide had used the LEED approach.

He added that BRE was in discussion with a number of other emerging Green Building Councils about adopting an assessment method based on the BREEAM framework but adapted to local circumstances. “With such a robust, well-established and internationally respected system of assessment already available to us, why would we want to change?” he asked. And indeed, the October meeting of the founding members confirmed that the UK GBC will use – and develop – the BREEAM suite.

The US report, conducted under contract with the US Energy Department’s Pacific Northwest National Laboratory, looked at five different methods of assessing whether a building design and construction is sustainable.

These were LEED, the Building Research Establishment’s Environmental Assessment Method (BREEAM); Green Globes US, Comprehensive Assessment System for Building Environmental Efficiency (CASBEE) and GBTool.

The reasons for its conclusions included the fact that LEED can be applied to all GSA project types – new and existing buildings, interior and other areas covered by USGBC standards. Also it “tracks the quantifiable aspects of sustainable design and building performance,” a major focus of federal programs under the impetus of the Government Performance and Results Act and a general demand for performance measurement.

Further reasons included the fact that trained professionals verify LEED and it has a “well-defined system for incorporating updates” which LEED is now undergoing through the LEED 3.0 update. And finally, it is also “the most widely used rating system in the U.S. market”.